Ovarian cancer has the highest mortality rate of the "women's cancers" (breast and gynecologic cancers). The Mayo Clinic SPORE in Ovarian Cancer features a team of basic, clinical, and population science Investigators conducting translational research designed to reduce the burden of ovarian cancer. The translational science of this SPORE includes four projects. Project 1, "Poisoning of PARP and topoisomerase I to treat ovarian cancer," studies the effect of the poly(ADP-ribose) polymerase (PARP) inhibitor ABT-888 alone and In combination with topotecan. In addition to elucidating how ABT-888 converts PARP Into an enzyme that actively contributes to the demise of topotecan-treated ovarian cancer cells, this project will examine a series of tumor markers for their ability to predict response in a topotecan/ABT-888 phase II trial. Project 2, "Mechanisms of immunosuppression in ovarian cancer," our population sciences project, studies the components of microenvironmental immunosuppression in ovarian cancer. Based in a large cohort of ovarian cancer cases, the work will examine differences in inherited variation in regulatory T-cell-related genes, the quantity of Tregs In the microenvironment and outcome after diagnosis. Project 3. "Optimizing measles virotherapy in the treatment of recurrent ovarian cancer," builds upon our in vitro and phase I clinical trial data showing promising anti-tumor activity with the attenuated vaccine strain of measles virus delivered intraperitoneally in women with recurrent ovarian cancer. In this project we will study the possibility of systemic administration of the virus and measures to enhance cytotoxicity of the virus. Project 4. "Flavopiridol reverses platinum resistance in ovarian cancer," builds upon work at Mayo showing that flavopiridol combines with cisplatin to yield cytotoxic synergy. We completed a phase I trial of this combination and now in a phase II trial in platinum-resistant ovarian cancer, have observed a 33% response rate, which is twice the mean response rate typically seen in this setting. This project will study the mechanism of synergy and attempt to improve upon the combination by adding a third agent and/or identifying predictive biomarkers in tumor samples from responders vs. non-responders. Four cores (Administration, Biospecimens/Patient Registry, Animal Models, and Biostatistics) provide the infrastructure support for the translational research of the SPORE. A Developmental Research Program has been established to foster promising research initiatives;and a Career Development Program will promote the research careers of junior or more established investigators who wish to pursue ovarian cancer translational research. The Mayo Clinic SPORE in Ovarian Cancer has the full support of the Mayo Clinic Cancer Center and Mayo Foundation.